In my mind Hangouts refers to the old school IM (Instant Message). Google Hangouts is used to converse with others through chat or video. Google Hangouts allows opportunities in the classroom by having guest speakers. It allows professional development when team members are not in the same building. Hangouts allows you to connect with others all over the world.
I personally have not used Google Hangouts much and I look forward to learning more about it. I currently use it to chat with my husband or other counselors across the district. I have used it to connect with relatives out of state as well. One way I plan to integrate Google Hangouts is by creating PLC (Professional Learning Communities) with the other counselors in my district so that we can fair share ideas and resources with each other.
Below is video telling a little more about Google Hangouts.